I searched all over online but can’t seem to find any info on fuel pump relay mounting. My pumps are low pressure Carter’s for carbs, only supporting 400hp each.

I understand the oil pressure switch, momentary bypass for priming the bowls, etc. but I can’t find any examples of where the relay is being installed?

Surely there is a spot on the engine on a newer efi Merc, but old school carb/distributor only type deals where is everyone mounting fuel pump relays? All the way up in the dash? Is no one using a relay? As I found it, mine is direct from ignition switch key on power... sketchy

I know it works, I guess I’m just surprised - seems a bit to shade tree mechanic but I’m so ingrained with safety from work (refinery equipment) that could a contributing factor!

I personally setup a painless fuse/relay block in my bilge that has 4 relay circuits and 3 continuous power circuits off of the fuse block. I tapped into the Merc purple wire to turn on the relayed circuits for ignition, pumps, etc and it cuts everything when the tether is pulled. The continuous circuits supply the stereo memory, bilge pumps etc. I found most of the stock wires to be rather undersized for any upgrades.

I decided to go with the dual relay I found at Concours Specialties ? Custom Switch Panels and Electrical Systems

No affiliation. I’ll let you know how it comes out. What sold me:

1. Waterproof housing
2. Integrated fuses
3. Pre-Wired

Those are nice systems. They have heavy enough wire that some apps need and plenty of wire for the bilge.